Universal time clock



Feb. 23, 1943. 'r. P. CONLON UNIVERSAL TIME CLOCK Filed Jan. 14, 1941 UNDDNA l NOME Patented Feb. 23, 1943 UNITED STATES PATENT OFFICE.

UNIVERSAL TIME OLOCK- Thomas P. .Conlon, New York, N. Y. Application January 14, 1941, SerialNo. 374,314

7 Claims.

My invention relates to improvements in universal time clocks, that is, clocks that are readily readable for the time in each of all the standard time zones throughout the world; and, the objects of my invention are, first, to providesuch scales, graduations, markings on the dial of the clock and such indicating mechanisms and in-v dicators to indicate on those markings and scales, to directly and immediately indicate the standard time in each and every zone, so that.

nated as a universal time clock, which correctly set for one zone, will indicate the time-with equal facility of reading in anyv other zone.

I attain these objects by the devices and mechanism illustrated in the accompanying drawing, in which:

Figure 1 is a front view of the preferred form of my invention, the view being taken looking atthe face of a clock adapted to indicate 'uni-. versal time; Fig. 2, a side View of the-same;- Fig- 3, an enlarged diagrammatic view of the star wheel and fictitious sunshown in Fig. 1;

Figure 4 is a view looking at the edge of the a hour disk adapted to carry a different form of fictitious sun; Fig. 5, a view from underneaththis form of hour disk; Fig. 6, a partial sectional edge view taken on the line VIVI, Fig. 4..

Figure 7 is a view of a modified formof the.

hour disk, the fictitious sun and the mechanism to operate the fictitious sun, part of the track and adjacent time zones being shown, but without designations for the zones, and withoutv numerals for the hours; Fig. 8, an'enlarged diagrammatic View of the switch, which is part of the operating mechanism shown in Fig. 7 Similar numerals refer to similar throughout the several views.

As my invention can be applied to a great variety of mean time clocks, both electric and mechanical, only part of the frame I, (Fig. 2)

is-shown. Many clocks space the dial plate '2 parts from this frame with spacers 3, 3, and insert between the two the train of gears to drive the hour hand from the movement of the minute hand, that is the pinion 4, pressed tight on the minute hand shaft 5, meshes with the gear 6.

The gear 6 and the pinion 1 are attached toon the minute hand shaft 5. The foregoing is one of the usual constructions now well known, but many others can be employed to drive the hour hand sleeve I0 atonetwelfth the speed of the minute hand shaft.

Also in the usual way the minute hand H, indicates upon the scale of minutes l2, graduated into minutes and each fifth minute made prominent and numbered towards the outside of the dial plate 2, as at l3.'

But this clock has no hour hand. In place thereof the hour hand sleeve It! carries an hour disk [4, which has the numerals for the twelve hours marked on the face of it, but in reverse order, that is in a counterclockwise direction, as at l5, and has an extension arm, I 8,-which' as shown in Fig. 2, forms a bearing for the pin IT, to which the star wheel I8 is attached. The small arm 19, carrying the glided representation 20 of a fictitious sun, is also attached to the pin l1, and is adapted to swivel through one hundred and eighty degrees, around the center of the pin, each time the star wheel I8 passes through what may be termed a gate formed by the three pins, 2|, 2|, 2|, which are driven into the dial plate 2.

By this mechanism and arrangement, and by marking off on the dial plate 2 twelve equal divisions by radial lines from the center of the minute hand, and separating each one of these divisions into two parts by the circles and lines as shown in the drawing as being roughly scribed by the path of the star wheel I8,"the

twenty-four standard time zones can be designated by zone names and by the names of prominent cities within such zones, as is shown in Fig. 1.

The position of the gateformed by the three pins 2|, 2| 2| will determine the position of" the zones in whichGreenwich, marked in Fig. 1 as London, and in which the date line falls; one of these zones is, as it were antipodal to the other.

The heavy black lines 22, 22, are provided in order to show clearly on the face of the clock the order in which the twenty four standard time zones have beenarranged in two series 01'. cycles of twelve hours each. Furthermore these heavy black lines have been made prominent in V The gear 9 and the hour hand sleeve It are attached together, and turn freely" order to facilitate the explanation for the general public of the method of reading the correct time in any zone. That explanation can be readily understood when it is explained that the places on the outside are to be read with the outside line, the places on the inside, with the inside line. That these lines, 22, 22, in reality represent one complete circle or cycle of 24 hours, the day, divided into two parts or cycles of twelve hours each, readable in hours from the hour disk. That visualizing the heavy black lines as the path or track of the fictitious mean sun, through twenty four time zones, the whole track must be considered as a continuous string looped upon itself. That the representation 29 can be considered as following the track, and indicating the zone where it is noon. That the hours, read from the hour disk I4, are postmeridian following the sun, that is, along the track, wheresoever it leads; antemeridian following the midnight. That the gap 23 indicates a crossing of the date line, and that a new dat along the track in a clockwise direction, from the date line on the inside track to the zone of midnight.

It is self evident that, without departing from the spirit of my invention, the hour disk, with, or without an hour hand located at the graduation for 12 oclock, but without the representation 20 of the fictitious sun, can be used by persons who understand how to read the noon and the midnight from the hour disk.

A modification in the mechanism that changes, at the date line, the fictitious sun to travel each track alternately is shown in Figs. 4, and 6. The device shown in these figures to represent the different radial positions of the fictitious sun consists of four small disks. Two of them are gilded, 20, 26, and two of them are black, 29a, 28a. They are aligned on the small shaft 24, as shown in Fig. 5, so that a gilded and a black disk appear on one side of this small shaft, while on the reverse side the colors are reversed in radial position.v The lugs 26, 26, attached to the hour disk I la, form a bearing for the rotation of the small shaft 24 and with the small pinion 25, which is firmly pressed on the small shaft, prevent end motion of that shaft. The small pinion 25 meshes with the rack segment 2?, attached to the dial plate I. The rack segment 2"! is aligned with the date line, and acts in place of the gate formed by the three pins 2!, 2i, 2%, but in this case the small shaft 24 is rotated through one hundred and eighty degrees in passing through the zone of the date line, and the gilded representation 20 of the fictitious sun with the black representation 20a on one side of the shaft 25 will reverse their radial position as the other side of the shaft is turned up on passing over the date line.

In the form of my invention shown in Figs. '7 and 8, a switch 39 is employed to change, for alternate revolutions of the hour disk Mb, the radial position of the fictitious sun 23 as it passes through the zone of the date line. The fictitious sun 20 is attached to the small rod 29, to which is also attached the cam roller 3 l. The small rod 29 is slidable in the lugs 25, 28, which are attached to the hour disk Mb. to which is also attached the guide 34, which prevents the rotation of the small rod 29. The pin 32', attached firmly to the dial plate 2, is a pivot on which the switch 38 can swing in a limited arc aiforded by the stop lug 33, which is also firmly attached to the dial plate 2. The switch 30 acts as a cam, upon which the roller 3! travels, as the date line is crossed, (by the fictitious sun), to shift the fictitious sun from the inside zones to the outside zones or vice versa. In Fig. 8 the alternate paths of the roller are shown at 3Ia and the dot and dash line through the center of that circle, and at MI) and the dot and dash line through this latter circle.

A great many other mechanical movements and principles can be employed to indicate the position of the noon or midnight in relation to two cycles of standard time zones without departing from the spirit of my invention. The

color, size, shape and position of the looped circles can be greatly varied, and other names and designations employed to indicate the several time zones, all without departing from the is to be read for the zones, reading spirit of my invention, and I can adapt it and apply it to either electric or mechanical timepieces. Furthermore, it is self evident that it applies to all timepieces, whether or not they have sweep or-separate second hands.

By my invention, the time in any zone, that is truly universal time, is as simple to read as the time in any other zone. Although I have shown in Fig. 1 the Eastern standard time zone at the top of the dial, any other zone could have been chosen for that position, the scale of minutes numbered for it, and all lettering made to conform. It will be seen that the Eastern standard time shown in Fig. 1 is 8 hours 6 minutes For brevity, neglecting the minutes, which are the same for all the zones, the track of the fictitious sun and its position thereon, makes the reading of the time at all places very simple; thus: 11 p. m. at Sydney; 1 p. m. at London; 5 a. m. at Los Angeles. And so for all the other zones, and places in them. The gap 23 at the date line greatly facilitates the solution of the question of date for which the reading of time is to be taken from the clock.

I claim:

1. A geographical clock comprising a clock work, a minute hand driven thereby, an hour disk co-axial therewith and driven thereby at the usual rate of one revolution in twelve hours, a dial plate behind said minute hand and hour disk having marked thereon twelve radial lines radiating from the axis of the minute hand and hour disk dividing said dial plate into twelve equal sectors, a minute circle dividing said sectors into twenty-four zones comprising an inner series of twelve zones and an outer series of twelve zones, each of which is marked to represent a standard time zone, said dial plate also having marked thereon at the appropriate location a line representing the international date line, said hour disk having marked thereon hour numerals 1 to 12 in counterclockwise sequence to indicate the hour in each time zone, and means mounted upon the hour disk to rotate therewith and movable with respect thereto for indicating the time zone in which it is noon.

2. A geographical clock comprising a clock work, a minute hand driven thereby, an hour disk co-axial therewith and driven thereby at the usual rate of one revolution in twelve hours, and a dial plate behind said minute hand and hour disk having marked thereon twelve radial lines radiating from the axis of the minute hand and hour disk dividing said dial plate into twelve equal sectors, a reference line dividing said sectors into twenty-four zones comprising an inner series of twelve zones and an outer series of twelve zones, each of which is marked to represent a standard time zone, the said reference line representing a complete cycle of twentyfour hours, said reference line consisting of two concentric arcs of somewhat less extent than a full circle co-axial with the minute hand and hour disk, said arcs lying between the two series of time zones, the ends of the arcs lying on opposite sides of the line representing the international date line, which with a minute circle is also marked on the dial plate, and each end of the inner are being joined to the opposed end of the outer are by a line, the lines joining opposed ends of the arcs intersecting at the line representing the international date line, a gap in one of the lines indicating a crossing of the date line.

3. A geographical clock comprising a clock work, a minute hand driven thereby, an hour disk co-axial therewith and driven thereby at the usual rate of one revolution in twelve hours, having the numerals 1 to 12 marked thereon in counterclockwise sequence, a dial plate behind said minute hand and hour disk, having a minute circle and twenty-four standard time zones marked thereon, the said standard time zones being arranged in two series, an inner series and an outer series, each of 12 zones. twelve radial lines dividing each series into the spaces for the twelve zones, a reference line dividing the inner series from the outer series and forming a boundary of each zone, the said reference line representing a complete cycle of twenty-four hours, and consisting of two concentric arcs of somewhat less extent than a full circle co-axial with the minute hand and hour disk, said arcs lying between the two series of time zones, the ends of the arcs being joined by crossed lines intersecting at the international date line, the said international date line being marked on the dial and its correct position being indicated by a gap in one of the crossed lines and means mounted upon the hour disk to rotate therewith and movable with respect thereto for indicating the time zone in which it is noon.

4. The combination in a geographical clock having a clock work and a minute hand driven thereby, of an hour disk co-axial therewith and driven thereby at the usual rate of one revolution in twelve hours and having marked thereon hour numerals from 1 to 12 in counterclockwise sequence, with a dial plate behind said minute hand and hour disk having marked thereon a minute circle and twelve radial lines radiating from the axis of the minute hand and hour disk dividing said dial plate into twelve sectors, and said dial plate having marked thereon a reference line dividing said sectors into twenty-four zones, each marked with geographical locations referred to standard time zones, the said reference line dividing these zones into an inner and an outer series of twelve zones each, the reference line indicating the sequence of time in the zones for a complete cycle of twenty-four hours, as the 12 hours are indicated by the hour disk, the said reference line being shaped somewhat similar to two concentric arcs, each approximating a full circle co-axial with the hour disk, the ends of the arcs being joined by crossed lines intersecting at the international date line marked on the dial plate, the correct crossing of the date line being indicated by a gap in one of the crossed lines.

'5. The combination in a geographical clock having a clock work and a minute hand driven thereby, of an hour disk co-axial therewith and driven thereby at the usual rate of one revolution in twelve hours and having marked thereon hour numerals from 1 to 12 in counterclockwise sequence, with a dial plate behind said minute hand and hour disk having marked thereon a minute circle and twelve radial lines radiating from the axis of the minute hand and hour disk dividing said dial plate into twelve sectors, and said dial plate having marked thereon a reference line dividing said sectors into twenty-four zones, each marked with geographical locations referred to standard time zones, the said reference line dividing these zones into an inner and an outer series of twelve zones each, the reference line indicating the sequence of time in the zones for a complete cycle of twenty-four hours, as the 12 hours are indicated by the hour disk, the said reference line being shaped somewhat similar to two concentric arcs, each approximating a full circle co-axial with the hour disk, the ends of the arcs being joined by crossed lines intersecting at the international date line marked on the dial plate, the correct crossing of the date line being indicated by a gap in one of the crossed lines, and means mounted upon the hour disk to rotate therewith and movable with respect thereto for indicating the time zone in which it is noon.

6. A geographical clock as claimed in claim 3, in which the means mounted on the hour disk to rotate therewith comprises an imitation representation of the fictitious mean sun movable with respect to the hour disk to indicate the time zone in which it is noon, and means for moving the same.

7. A geographical clock as claimed in claim 3, in which the means mounted on the hour disk to rotate therewith comprises imitation representations of a fictitious mean sun and imitation representations of midnight and means for moving such representations to indicate the proper time zones marked on the dial plate in which it is noon and in which it is midnight.

THOMAS P. CONLON. 

